A CPU cache is a cache used by the central processing unit of a computer to reduce the average time to access memory. The cache is a smaller, faster memory which stores copies of the data from the most frequently used main memory locations. As long as most memory accesses are cached memory locations, the average latency of memory accesses will be closer to the cache latency than to the latency of main memory.
A cache memory is a cache used by a processing unit, or core, of a computer to reduce the average time to access memory. It is generally faster to store and retrieve memory from the cache than from main memory. When a processor core needs to read from or write to a location in main memory, it first checks whether a copy of that data is in the cache. If so, the processor immediately reads from or writes to the cache, which is faster than reading from or writing to main memory. A multi-core node is composed of two or more independent processing cores. The cores are typically integrated onto a single integrated circuit die, or they may be integrated onto multiple dies in a single chip package, or substrate. An extended memory cache extends the hardware-based cache located on the node substrate to system memory to extend the amount of memory available in the cache.